MVC is the separation of model, view and controller — nothing more, nothing less. It’s simply a paradigm; an ideal that you should have in the back of your mind when designing classes. Avoid mixing code from the three categories into one class.
For example, while a table grid view should obviously present data once shown, it should not have code on where to retrieve the data from, or what its native structure (the model) is like. Likewise, while it may have a function to sum up a column, the actual summing is supposed to happen in the controller.
A ‘save file’ dialog (view) ultimately passes the path, once picked by the user, on to the controller, which then asks the model for the data, and does the actual saving.
This separation of responsibilities allows flexibility down the road. For example, because the view doesn’t care about the underlying model, supporting multiple file formats is easier: just add a model subclass for each.